Unilocular

Unilocular is an adjective used in biology to describe a structure that has a single locule or cavity. The term derives from Latin unus, meaning one, and loculus, meaning a small place or cavity. It is commonly applied in botany to ovaries and fruits, where the locule is the chamber that contains ovules or seeds. The counterpart terms are multilocular, meaning having more than one locule, and bilocular, meaning having exactly two locules.

In botanical usage, an ovary may be unilocular, containing a single chamber. When such an ovary develops into a fruit, the resulting fruit is described as unilocular. The number of locules is a diagnostic feature used in plant identification and classification, and it can influence the internal arrangement of seeds within the fruit.

Examples commonly cited in botany include drupes, which often originate from unilocular ovaries and typically contain a single seed, as with peaches, cherries, and olives. By contrast, many simple berries develop from ovaries with multiple locules, producing a fruit with several seed-bearing compartments, such as some varieties of tomatoes.

In summary, unilocular denotes a single-cavity structure, most often discussed in the context of plant ovaries and fruits, where the locule count aids in describing morphology and taxonomy.